You have to calm them down somehow. This situation is not only bad for a potential alliance, but for their relationship.
"It doesn't matter. It's in the past and there's nothing we can do to change it." you start, as the two of them stop to look in your direction. "The Tsuchikage made the decision that he felt was best, and things didn't work out. The Leaf has made mistakes regarding its Jinchuuriki as well. The fact is that we ended up having to cooperate against Akatsuki regardless. This alliance is our opportunity to fix any mistakes that may have been made before. Kurotsuchi, even if you don't agree with the Tsukage's decisions, they're still worthy of respect. You should just be learning from him, so you can make the right decisions in the future. Lord Tsuchikage, I know you've been through a lot, but even a Kage can't do everything on their own. I know I've had to face my limits several times. What's important is having other people to rely on when there are things you can't do. I think with this alliance, we can prove ourselves to you."
Kurotsuchi backs off. She looks a bit calmer, but still irritated.
"Sorry, I need to excuse myself." she says as she leaves the room.
The Tsuchikage turns to you.
"Kon, you're a fine young man, and I have faith in you. You're like your father." he starts. "But relying on other villages is not something I can so easily do. However I will try, for now. You have my cooperation."
The meeting over, you leave the office to find Neji outside.
"I saw Kurotsuchi leave in a hurry." he remarks. "Did the meeting go well?"
>A.It went perfectly, we've got an alliance>B.It went alright, Kurotsuchi just overreacted>C.It wasn't so good, we've got a long way to go>D.Other